iPhone X, XS and XR: what separates them now
The XR is usually the strongest of the three today. Its LCD panel is cheap to replace, its battery was large to begin with, and it sold in huge numbers here, so buyers still look for one. It sits one release cycle behind the iPhone 11 on Apple's support list, close enough that shoppers compare the two.
The iPhone X is the weakest, and its screen is the reason. It was Apple's first OLED iPhone, and aged units commonly show burn-in or a green line. Either fault drops the offer sharply, because the panel has to be replaced.
The XS and XS Max sit between: better cameras and a stainless frame than the XR, but the same small battery and the same place on the update list.
The iPhone SE punches above its looks
Do not judge an SE by the home button. The 2020 model uses the same A13 chip as the iPhone 11 and the 2022 model the A15 from the iPhone 13, so both stayed on Apple's software list far longer than phones that look newer.
That matters for price. A well-kept SE from either year can be worth more than an iPhone X, even though the X launched as a flagship and the SE never did.
The original 2016 SE is a different story entirely and belongs with the group below.
iPhone 8, 7, 6 and earlier: honest expectations
From the iPhone 8 downwards you are in low-value territory. The 8 and 8 Plus still have wireless charging and a working Touch ID button, so they carry a small but real price. The 7, 6s, 6 and earlier are worth roughly what their parts are worth, and not much more.
We still take them. Nobody is turned away with an iPhone 6 or a 4s — just arrive expecting a modest number rather than a surprise.
The practical advice is to bundle. One trip with five old phones is worth your afternoon. One trip with a single iPhone 6 usually is not.
Activation Lock is what stops these sales
We cannot pay for an iPhone still locked to an Apple Account, and old phones are the most likely to be locked, because the password was set years ago and forgotten. It is the single most common reason someone walks in with an old handset and walks out still holding it.
If the phone powers on, sign out of iCloud in Settings and erase it from Settings, General, Transfer or Reset iPhone. If it will not power on, or the screen is unreadable, clear it from another device: sign in at iCloud.com with the same Apple Account, open Find My, select the phone and remove it from the account. Doing that before you travel turns a wasted trip into a sale.
If the phone was a family member's, log in as them rather than guessing. If nobody can reach that account, there is no route anyone can take, and the handset is worth only its parts.